Semitrailer jack



Nov, 27 1923.

J. MORRISQN SEMI'IRAILER JACK Filed Jan. 26. 1920 2 Sheets-Sheet 1 J. MORRHSON SEMITRAILER JACK Filed Jan. 26. 1920 2 Sheets-Sheet 2 A {torn 6y;

Patented Nov. 27, 1923.

UNITED STATES PATE T oluucs.

. JAMES MORRISON, OF CINCINNATI, OHIO, ASSIGNOR TO TRATLMOBILE COMPANY,

OF-CINCINNATI, OHIO, A CORPORATION OF OHIO.

SEMIT RAILEB, JACK.

Application filed January 26, 1920. Serial No. 854,228.

I To all whom it may concern:

' Be it known that I, JAMES MonnIsoN, a citizen of the United States, and a resident of the, city of Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in- Semitrailer Jacks, of which the following is a full, clear, and exact description,'reference being had to the drawin'gs,forming a part of this specification. v

My. invention-relates to jacks of a type which are particularly adapted for use with semi trailers, in order, to support the front end of the trailer when the tractor has been disconnected therefrom.

The semi trailer, as customarily so called, is a trailer vehicle provided with rear wheels only, and in which the forward end is supported on the rear of a short framed tractor. As is readily apparent there must be some means provided in connection with such a vehicle, to support. the front end thereof whenthe tractor has been withdrawn, and my-invention applies tothe provision of a jack mechanism forthis purpose.

The jack as used in semi-trailers is one of the most important considerations in the vehicle construction, and on the form ofjack employed in many instances rests the practicabilityof the entire trailer construction.

- A number of special features are necessary for semi-trailer jacks, which are not to be found in normal jack construction.

In the first place it must be a permanent fixture of the trailer, because of'its absolute necessity, and being a permanent fixture, it

must be capable of a quick adjustment, as well as a slow one, so that the necessary jack adjustments for supporting the load may be quickly made, with the tractor in place and so that the lifting of the load, to accommodate the position of the trailer to ready b l'hdb th .I.; l couplmg may accomp 18 e y e usl'm lower flange of the channel bars is securely slow motion.

It is also-quitevaluable to have the jacks swing into and out of supporting position,

and to have the joint necessary to accomplish this movement of a-character which will not llt isthe object of my invention herein to provide a semi-trailer jack which provides for the above features in 1ts construction,

and in addition to provide a'jack' assembly for both sides of the device, which have a joint action, and convenient modes of opera-' tlon.

These objects and other advantages I accomphsh by that certain construction and arrangement of parts to be hereinafter more specifically pointed out and claimed.

In the drawings,

Figure 1 is a assembly.

perspective view of the jack.

Figure 2 is a side elevation of the' same parts showing the jacks raised and unlocked. Figure 3 is a detail sectional view showing the pawl tripging device.

Figure 4' heet 1) is a detail section taken through the jack raising device.

Figure 5 is a vertical section of the jack foot.

. Q Figure 6 is a plan view of the section shown in Figure 5.

Figure 7 is .a side elevation of the ball member of the jack foot.

Figure 8 is a detail rear elevation of the con ecting means between the two jack housin v or sockets.

Figure 9 is a detail side elevation showing flanges 2, which'are riveted to the channel bars of the frame, and with inwardly extending flanges 2", strongly buttressed, as at 2, which underlie the channel bars 1. An

angle bar 2, crooked up at 2, to lie on the riveted to the flanges 2?, and extends across between the two housing devices. This construction relieyesthe frame of the vehicle from weaving, under the influence of the jacks. since the jacks as will be noted, are

provided with feet which rock with relation to the balance of the jack structure.

The jack screws 3, 3, have right and left hand threads and are operated by any desired device. A ratchet 3 may be aflixed to the screws to be engaged by a reversable ing bar, and in addition, extending fromin sleeves 4, and the pawl handles 5, for rej b versing the pawls.

On the sleeves are the usual socketed arms 6, for recelving, when necessary, an operat each sleeve is a bifurcated arm 7, the two arms for the two jack constructions being connected by a cross bar 8, pivoted to each arm.

The interiorly threaded jack posts 9, receive the jack screws and when held against revolution by contact with the supporting surface, will be forced longitudinally by the revolution of the screw in the ordinary and well known manner. Furthermore, this revolution, may be imparted to both screws at the same time, due to the interconnection of the two arms 6. 7

Itis desired to provide the jacks with hinged ends or posts and to swing these posts rearwardly at the hinge so as to quickly move them out of the'way during operation of the vehicle. The rearward motion is necessary in order to keep the jacks or their operating parts from interference with the tractor vehicle, or such form of fifth wheel as is used between the trailer and tractor, and since this motion is necessary, it becomes of importance to provide a form of hinge which will not fill with mud or filth that is thrown rearwardly from the tractor wheels.

Accordingly the lower end of the interiorly threaded jack posts are formed with semicylindrical depending flanges 10, which are apertured to receive pivoting bolts 11-, this aperture being for each jack located rearwardly of the center line of the said posts.

The hinged jack posts or extensions 12, are swung from these pivot bolts, and when moved upwardly and rearwardly the flanges of the threaded post will prevent dirt from accumulating behind the hinged joint.

The lower ends of the jack posts are fitted with collars 13, which support balls 14, the balls having peripheral lugs 15 thereon to prevent turning. The feet 16 of the jacks are socketed at 17 to receive the balls, but are grooved in addition at 18 to receive the lugs on the balls.

By making the grooves 18 considerably wider than the lugs there will be a fairly complete universality ofthe joint at the foot, to allow for uneven supporting surface, and at the same time the body of the jack will not turn sufficiently,-upon revolution of the lifting screw, when a load is supported, to prevent the normal jack operation.

It is desirable to provide some means for locking the hinged joint of the jack, and as a convenient gravity means I provide the hinged posts with lugs 19, and hinge to the threaded jack posts, pawls 20, which will fall by gravity to a position or abutment against the flat upper surface of the lugs, which will prevent any rearward flexing of the oint. The forward flexing is prevented by the flanges of the upper post element, striking the sides of the lower post element. The pawls serve to retain the hinged jack legs in position against the protecting flanges of the posts 9, and thereby provide a very strong and stiff construction for maintaining the legs in a locked vertical position.

so lifted that the weight is no longer supported by the jack feet, and the pawls are withdrawn. This saves the operator from the necessity of holding the pawls out, once they have been jerked away.

I preferably mount over the connecting rod between the two jack operating arms 7,

' the rotatable sleeve 21, which has an arm 22 at each end. From the arms depend chains 23, which have extra links 24, therein, beyond those ordinarily needed these chains being connected at their lower ends with the pawls by means of snap hooks 25. The chains may thus be readily disconnected to permit the usual turning of the jack sleeves and the operator need but jerk upwardly on one of the arms 22, to raise bot-h pawls entirely free from their looking or abutment position. When the jacks are lengthened out in their preliminary adjustment, theextra links come into play to connect up the pawls.

An alternative construction, for locking the hinged joint of the jack legs is shown in Figure 9. In this construction the jack posts have the protecting or abutment flange 40, with an additional lip 41 at the forward end thereof. The jack legs are pivoted or hinged as above noted, and have formed adjacent the pivot point, a pair of lugs or trunnions 42, which support a stirrup :43. This stirrup is under the influence of coiled springs which tend to throw them upwardly, and are suitably stopped against excessive upward movement by lugs 44 on the trunnions. According to this construction the stirrups latch automatically over the projecting lips on the abutment flanges, and may be individually or jointly dislodged from locking position, according to any special construction that may be desired.

Located on the trailer frame, at each side, and to the rear of the jack sockets, are plates 26, one of 'which carries an apertured se ment 26*. At the lower end the lates, 1s

. journaled a shaft Q5 having arms 2 whose i at the ball joint, so as to permit the rotation of the jack and have extra links for the same reason as in the pawl chains.

The arm which is on the side of the, seg-. ment, has an operating handle 33, which carries centrally a pin 34, that projects through the arm. This pin operates to engage in the selected hole 35 in the segment.

For providing a spring mounting for the handle, it is hollow, and has a flange 36 at its inner end. A core 37 mounted on the arm, .and through which passes the segment engaging pin, has a matching flange 38, thereby providing a space for a coiled spring .39. This spring permits the sliding of the handle proper, under sprlng tension, and permits of the manipulation of the segment engaging pin.

For raising both jack posts on their hinges, the operator first jerks the pawls out of the way and then operates the arm or crank 27,

which will wind up both post chains, and swing the lower post section" and their feet up out of the way for operation of the vehlcle.

The p erating device above described is of peculiar y advantageous nature. In the first place it permits the posts of the jack to be revolved manually without disc lengthening or shortening either chain, should the supporting. surface require unequal jack adjustment. In the next place it provides for a quick operation, since the chains are connected to the ends of the arms or cranks, instead of to the reels on the cross shaft. The reels and deflectors keep the chains away from the arms so as notto interfele with their operation, andrthe line of motion of the cranks, at their first quarter revolution is about on a line with the natural line of movement of the ends of the jack le S.

This makes the operation of raising the legs an easy one, whereas connection to the reels direct would not.

, When referring to forwardly and rearwardly with relation to the hinge of the jacks, it should be understood that this is a relative term, and. is intend d to mean for-- purpose, these ends aging the 'chai.ns along with the adapta ility for wardly or rearwardly of the center line dravm through the two jack screws, since it is obvious that an exact parallelism with the frame of the vehicle,-m1ght even be undesirable in some instances, all that is necessary being that the jacks do not fill with dirt at. the joints, and do not interfere with the tractor parts when folded or raised.

The operation of the jacks has been described above, but it should be noted that the structure described adapts itself to adjustment for any supporting surface that is likely to be met. stops his vehicle first adjusts the jacks man'- ually turning them around without load thereon, until each foot is in position adjacent the supporting surface. He then re moves the tractor, and his jacks are ready for joint operation by therevolutionof the pawl carners l, without resultingin a tipping of the vehicle in any respect, and with equal load on the two jacks.

While adjusting the jacks he will unsnap the pawl chains, and after extraordinary adjustment which takes up the slack in any chain, will connectup such chain so that it will operate together with its companion.

lt is, not desired that the claims which follow be limited in construction due to my failure above to point out in every instance J the possibility of mechanical changes for the parts described.

Having thus described my invention, what ll claim as new and desire to secure by Letters Patent is 1. In a semi-trailer jack devicefthe combination of a pair of jacks. one rigidly mounted on each side of a vehicle and ad justable to and from the vehicle, hinged legs for said jacks, pawls for locking the hinged legs in vertical position, and a common operating device for withdrawing said pawls operable from one side of the vehicle, at least. a

2. In a semi-trailer jack device, the combination of a pair of jacks, one ri 'dly mounted on each side of a vehicle an adjustable to and from the vehicle, hinged legs for said jacks, pawls for locking the hinged .legs in vertical position, and a common operating device for withdrawing said pawls operable from one-side of the vehicle at least comprising a rock shaft, mounted across the vehicle, arms on saidshaft and chains from said arms connected to the pawls.

3. In combination with a vehicle frame, a pair'of jacks permanently mounted thereon and adjustable to and from the vehicle, hinged legs for said jacks, chains for raising said hinged legs, a cross shaft on the vehicle, a chain accumulating device on said shaft comprising at least in part arms the ends of which. are connected to the chains,

The, operator when he and means on the shaft for operating the In same, whereby said two legs may be simultaneously lifted.

4. In combination with a vehicle frame, a pair of jacks permanently mounted thereon, hinged legs for said jacks, chains for raising said hinged legs, a cross shaft on the vehicle, a pair of arms on said shaft, with which arms the chains are connected, and chain accumulating reels at the base of the arms, one of said arms at least having means for looking it in desired position to maintain the chains in reeled up condition.

5. In combination with a vehicle frame, a pair of screw jacks, mounted thereon, with the lower ends of said jacks revoluble on the screws thereof, hinged legs for said lower portions of the jacks, and means in common with both jacks for raising the hinged legs,

said means being adapted to permit revolution of the legs together with the lower portions of the jack, for the purpose described.

6. In combination with a vehicle frame, a

pair of jacks mounted thereon, with the adapted to permit revolution of the jack portions, for the purpose described.

7. An operating device for lifting the leg of a hinged jack on a vehicle comprising a crank on the vehicle, a chain connected to the crank and the jack leg, a segment on the vehicle, means on the crank for engaging the segment, and chain accumulating. means at the base of the crank.

8. An operating device for lifting the leg of a hinged jack on a vehicle comprising a crank on the vehicle, a chain connected to the crank and the jack leg, a segment on the vehicle, means on the crank for engag ing the se cut, and chain accumulating means at t e base of the crank, said last means comprising a channeled reel device at said base of the arm, and a. lip extending inwardly across the channel to guide the chain against slipping off the reel, as and for the purpose described.

9. In a semi-trailer jack device, the com-.,

each side of a vehicle, hinged legs for said jacks, pawls on the acks for locking the hinged legs in vertical position, and a common operating device for withdrawing said pawls operable from one side of the vehicle at least, said common operating device being disconnectible from the pawls, for the purpose described.

11. In a semi-trailer jack device, the com bination of a pair of jacks one mounted on each side of a vehicle, hinged legs for the jacks, locking devices for maintaining the legs in vertical position on the jacks, a common operating device for the jacks compris-' ing in part a connecting rod between two operating devices, a sleeve on said rod, and adapted to be rocked thereon, and connection from said sleeve to the leg locking devices for joint operation thereof, upon rocking of said sleeve.

' 12. In combination with a vehicle frame, a pair of screw jacks permanently mounted thereon and each having a depending member threaded on the screws thereof, hinged legs on said depending members, and a common operating device for jointly lifting said legs comprising in part flexible elements loosely connected to the legs above the feet thereon to permit revolution thereof.

13. In combination with a vehicle frame, a pair of jacks permanently mounted thereon, and adjustable to and from said frame, a hinge for a portion of the jacks at least, a cross shaft on the vehicle, arms on said shaft, flexible members connected to the hinged portion of the jacks and to a oint substantially at the ends of the arms, w ereby said chains may be accumulated on the said shaft, by a revolution of the cranks, with the first motion of the cranks directly moving the legs through a substantial arc.

14. In a semi-trailer jack device, the-com bination of a pair of jacks each comprising in part an operating device and a. supporting surface engaging element adjustably mounted on said operating device, means for mounting the operative device on 58. frame portion of a vehicle, means whereb said surface engaging elements may be a justed to an angular position without afi'ecting the operating devices, and means connecting theoperating devices for o1nt operation. for the purpose described.

15. In a device of the character described, the combination with a air of jacks mounted on each side of a vehicle, socket members mounted on the vehicle and constituting the mounting elements for said jacks, and means secured to and interconnecting said socket members and extending across the vehicle to provide a brace for the upper end of said jack structures.

16. In a device of the character described, the combination with a vehicle frame, of a pair of jacks mounted one on each side of naraeea the frame and comprising in part socket members to be secured to the frame, and means interconnecting the jacks at their point of connectionwith the frame to provide a brace for the jack assembly in addition to the frame.

17. The combination with a trailer, of two jacks connected with the respective sides of the said trailer and each comprising an upper member and a lower member pivotally connected with said upper member for movement into and out of alignment therewith, the upper member of each jack comprising two parts having right and left hand screw threads, a screw threaded into said parts, a

toothed wheel secured to said screw between the two parts of said upper member, a housing mounted for rotation about the axis of said screw, a pawl yieldably mounted in said housing to engage the teeth of said wheel, a lever socket connected with said housing, an arm projecting from said housing, a connecting bar extending between the arms of the two jack, whereby the manipulation of one jack will cause similar manipulation of the other jack.

J S MURRISUN. 

